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2000年来吕梁连片贫困区植被净初级生产力时空变化特征 总被引:1,自引:0,他引:1
多年来吕梁连片贫困区实施的生态恢复措施对其生态环境产生了较大影响,为掌握该区域在生态恢复措施实施(2000年)以来植被净初级生产力的变化状况,利用2000—2018年时序的遥感数据和基于光能利用率的CASA模型对其进行了模拟,并分析了导致其变化的主要控制因素,结果显示:(1)2000年以来吕梁连片贫困区NPP整体上升,其中93.46%的区域NPP呈增长状态,6.54%的区域呈减少状态,2010—2015年区域NPP出现下降。(2)受人类活动影响,过去18年来区域土地利用类型变化较为显著,耕地面积缩减,草地面积基本保持稳定,林地与城镇面积增加且城镇面积扩张迅速,不同土地利用下的NPP特征差异显著,耕地NPP年均值增长最为迅速,为5.9 gC m-2 a-1,林地最为平稳,为1.32 gC m-2 a-1。(3)研究区降水量波动对区域NPP的变化影响显著,未来气候变化中降水量的变化可能对区域NPP产生直接影响。研究结果将为区域生态恢复、精准扶贫及黄河中游地区的经济发展提供重要的理论支撑。 相似文献
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Huan Zhang Shanshan Zhu Tianzhen Liu Chunming Wang Zhijun Cheng Xin Zhang Liping Chen Peike Sheng Maohong Cai Chaonan Li Jiachang Wang Zhe Zhang Juntao Chai Liang Zhou Cailin Lei Xiuping Guo Jiulin Wang Jie Wang Ling Jiang Chuanyin Wu Jianmin Wan 《Plant biotechnology journal》2019,17(2):531-539
Heading date is an important agronomic trait affecting crop yield. The GRAS protein family is a plant‐specific super family extensively involved in plant growth and signal transduction. However, GRAS proteins are rarely reported have a role in regulating rice heading date. Here, we report a GRAS protein DHD1 (Delayed Heading Date1) delays heading and enhances yield in rice. Biochemical assays showed DHD1 physically interacts with OsHAP5C/D both in vitro and in vivo. DHD1 and OsHAP5C/D located in the nucleus and showed that rhythmic expression. Both DHD1 and OsHAP5C/D affect heading date by regulating expression of Ehd1. We propose that DHD1 interacts with OsHAP5C/D to delay heading date by inhibiting expression of Ehd1. 相似文献
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目的 探究长链非编码RNA(lncRNA)ZNF667-AS1通过靶向miR-31-5p对食管癌细胞增殖和迁移的影响及潜在的机制.方法 采用实时荧光定量PCR(qPCR)技术检测ZNF667-AS1在食管癌细胞Eca109、EC1、TE1和正常食管上皮细胞Het-1A的表达水平,并选择表达差异最大的细胞株进行后续实验.... 相似文献
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Identification of a stable quantitative trait locus for percentage grains with white chalkiness in rice (Oryza sativa) 总被引:1,自引:0,他引:1
Guo T Liu X Wan X Weng J Liu S Liu X Chen M Li J Su N Wu F Cheng Z Guo X Lei C Wang J Jiang L Wan J 《植物学报(英文版)》2011,53(8):598-607
High chalkiness is a major problem in many rice-producing areas of the world, especially in hybrid rice (Oryza sativa L.) in China. We previously showed a major quantitative trait locus for the percentage of grains with white chalkiness (QTLqPGWC-8) in the interval G1149-R727 on chromosome 8 using a chromosome segment substitution line (CSSL). Here, we selected the line-CSSL50 harboring the QTLqPGWC-8 allele from the CSSLs derived from a cross between Asominori (as a recurrent parent) and IR24 (as a donor parent), which had higher percentage chalkiness, markedly different from that of Asominori. There were also significant differences in starch granules, appearance of amylose content (AAC) and milling qualities between Asominori and CSSL50, but not in grain size or thousand grain weight (TGW). The BC(4) F(2) and BC(4) F(3) populations from a cross between CSSL50 and Asominori were used for fine mapping of qPGWC-8. We narrowed down the location of this QTL to a 142 kb region between Indel markers 8G-7 and 8G-9. QTLqPGWC-8 accounted for 50.9% of the difference in PGWC between the parents. The markers tightly linked to qPGWC-8 should facilitate cloning of the gene underlying this QTL and will be of value for marker-assisted selection in breeding rice varieties with better grain quality. 相似文献
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Jiulin Xia Kevin Mattison Vincent Romano Paul L. Dubin Barry B. Muhoberac 《Biopolymers》1997,41(4):359-365
Complexation of alcohol dehydrogenase (ADH) and trypsin with poly(diallyldimethyl-ammonium chloride) (PDADMAC) in dilute electrolyte solution was studied by turbidimetric titration, quasi-elastic light scattering (QELS), and electrophoretic light scattering (ELS). Both QELS and turbidimetric titration show that PDADMAC forms complexes with ADH and trypsin in 0.01M NaCl solution at pH ≥ 6.8 and pH ≥ 9.2, respectively. These complexes take the form of stable coacervates in 0.01M, pH 11.0, phosphate buffer solution. QELS shows sizes of 400 and 315 nm for the coacervates of ADH-PDMDAAC and trypsin-PDMDAAC, respectively, while ELS reveals that these coacervates carry a net positive charge. Activity measurements show that both ADH and trypsin are enzymatically active in their coacervated states. Complexation of trypsin and PDADMAC was also studied by fluorescence in 0.01M, pH 11.0, phosphate buffer, and the protein emission was found to be quenched by complexation. The fluorescence quenching data show that trypsin retains its three-dimensional structure in the complex. These and other results are consistent with the quenching of the two tryptophans on the protein surface, but not the interior ones.© 1997 John Wiley & Sons, Inc. 相似文献
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Jiulin Xia Paul L. Dubin Etsuo Kokufuta Henry Havel Barry B. Muhoberac 《Biopolymers》1999,50(2):153-161
Quasi‐elastic light scattering (QELS), electrophoretic light scattering (ELS), CD spectroscopy, and azide binding titrations were used to study the complexation at pH 6.8 between ferrihemoglobin and three polyelectrolytes that varied in charge density and sign. Both QELS and ELS show that the structure of the soluble complex formed between ferrihemoglobin and poly(diallyldimethylammonium chloride) [PDADMAC] varies with protein concentration. At fixed 1.0 mg/mL polyelectrolyte concentration, protein addition increases complex size and decreases complex mobility in a tightly correlated manner. At 1.0 mg/mL or greater protein concentration, a stable complex is formed between one polyelectrolyte chain and many protein molecules (i.e., an intra‐polymer complex) with apparent diameter approximately 2.5 times that of the protein‐free polyelectrolyte. Under conditions of excess polyelectrolyte, each of the three ferrihemoglobin–polyelectrolyte solutions exhibits a single diffusion mode in QELS, which indicates that all protein molecules are complexed. CD spectra suggest little or no structural disruption of ferrihemoglobin upon complexation. Azide binding to the ferrihemoglobin–poly(2‐acrylamide‐2‐methylpropanesulfonate) [PAMPS] complex is substantially altered relative to the polyelectrolyte‐free protein, but minimal change is induced by complexation with an AMPS‐based copolymer of reduced linear charge density. The change in azide binding induced by PDADMAC is intermediate between that of PAMPS and its copolymer. © 1999 John Wiley & Sons, Inc. Biopoly 50: 153–161, 1999 相似文献
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Zhou Kunneng Ren Yulong Zhou Feng Wang Ying Zhang Long Lyu Jia Wang Yihua Zhao Shaolu Ma Weiwei Zhang Huan Wang Liwei Wang Chunming Wu Fuqing Zhang Xin Guo Xiupin Cheng Zhijun Wang Jiulin Lei Cailin Jiang Ling Li Zefu Wan Jianmin 《Planta》2017,245(1):45-60
Planta - Young Seedling Stripe1 (YSS1) was characterized as an important regulator of plastid-encoded plastid RNA polymerase (PEP) activity essential for chloroplast development at rice seedling... 相似文献
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Albino midrib 1, encoding a putative potassium efflux antiporter,affects chloroplast development and drought tolerance in rice 总被引:2,自引:0,他引:2
Peike Sheng Junjie Tan Mingna Jin Fuqing Wu Kunneng Zhou Weiwei Ma Yueqin Heng Jiulin Wang Xiuping Guo Xin Zhang Zhijun Cheng Linglong Liu Chunming Wang Xuanming Liu Jianmin Wan 《Plant cell reports》2014,33(9):1581-1594